Justification This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Family/Sub-family Ardeidae

Species name author Linnaeus, 1766

Taxonomic source(s) AERC TAC (2003), Cramp and Simmons (1977-1994), Dowsett and Forbes-Watson (1993), Sibley and Monroe (1990, 1993)

Taxonomic note Ardea purpurea (Sibley and Monroe 1990, 1993) was split into A. purpurea and A. bournei by Hazevoet (1995). This treatment is not followed by the BirdLife Taxonomic Working Group although we do recognise consistent behavioural differences and that bournei is paler overall in colouration.

Population estimate

Population trend

Range estimate (breeding/resident)

Country endemic?

270,000 - 570,000

unset

22,400,000 km²

No

Important Bird Areas Click here to view map showing IBAs where species is recorded and triggers any of the IBA criteria.

Ecology: Behaviour Populations breeding in the western Palearctic are migratory¹ and travel on a broad front between breeding and wintering grounds². African and tropical-Asian populations are largely sedentary however, occasionally making local dispersive movements¹. The species breeds from April to June in the western Palearctic, during the rains in Africa, and from June to October in the north of India or November to March in the south of India¹. It is a colonial breeder^{1, 2, 3, 4} and although nesting group sizes are usually small (e.g. 2-3 pairs per colony in Africa) and rarely exceed 50 pairs³, colonies of up to 1,000 pairs have been recorded in some areas^{1, 4}. It often also nests on the periphery of colonies of other heron species such as Grey Heron Ardea cinerea². In migratory populations the autumn migration occurs from August to October⁴, with the return passage in the spring beginning in March⁴. On migration the species commonly occurs in small groups (the maximum recorded migratory groups sizes being 300-400 individuals)¹ and throughout the year it will roost communally by day and by night⁴ in groups of up to 100 individuals⁵ although it generally feeds solitarily^{1, 4}. The species is mainly crepuscular, but may also feed diurnally¹. Habitat The species inhabits wetlands from sea level to 1,800 m (Madagascar)¹, showing a preference for dense, flooded, freshwater reedbeds (Phragmites spp.) in temperate areas (occupying Typha, Scirpus and Papyrus swamps elsewhere)². It also utilises lake shores, river margins¹, ditches, canals, brackish water lagoons², rice-fields, mangroves and coastal mudflats¹. Diet Its diet consists of fish 5-15 cm long¹ (occasionally up to 55 cm), salamanders², frogs, insects¹ (e.g. beetles, dragonflies, hemiptera² and locusts⁴), crustaceans¹, spiders² and molluscs⁴ as well as small birds and mammals, snakes and lizards¹. Breeding site The nest is a platform of reeds stems or sticks² positioned over or beside water up to 3 m high in flooded reedbeds¹, 3-4 m high in thickets or mangroves² or up to 25 m high in trees¹. The species usually nests in loose single- or mixed-species colonies with Grey Heron Ardea cinerea, and although colony sizes are usually small, large groups of up to 1,000 pairs have been recorded^{1, 4} (the colony size depends on the size of the area of marshland)². Management information Studies in southern France have shown that the overall conservation of this species in Europe is favoured by maintaining large uncut reedbeds with relatively high spring water levels⁷.

Threats The main threat to this species in Europe is the loss of reedbeds though direct elimination (to reduce sedimentation)², agricultural encroachment⁶, water management practices² (e.g. drainage)⁶ and reed cane harvesting².

References 1. del Hoyo et al. (1992). 2. Kushlan and Hancock (2005). 3. Turner (2000). 4. Hancock and Kushlan (1984). 5. Brown et al. (1982). 6. Hockey et al. (2005). 7. Barbraud et al. (2002).

Further web sources of information

Detailed species account from Birds in Europe: population estimates, trends and conservation status (BirdLife International 2004)

Text account compilers Stuart Butchart (BirdLife International), Jonathan Ekstrom (BirdLife International), Lucy Malpas (BirdLife International)

IUCN Red List evaluators Jeremy Bird (BirdLife International), Stuart Butchart (BirdLife International)

Recommended citation BirdLife International (2010) Species factsheet: Ardea purpurea. Downloaded from http://www.birdlife.org on 30/7/2010

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

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